The present invention relates to the field of submersible pump assemblies, and more particularly but not by way of limitation, to an in situ separable electric submersible pump assembly with a latch device.
In oil wells and the like from which the production of fluids is desired, a variety of fluid lifting systems have been used to pump the fluids to surface holding and processing facilities. It is common to employ various types of downhole pumping systems to pump the subterranean formation fluids to surface collection equipment for transport to processing locations.
One such prior art pumping system is a submersible pumping assembly which is supported immersed in the fluids in the wellbore. The submersible pumping assembly has a pump and motor to pressurize and pass the reservoir fluids through production tubing to a surface location.
In straight and deviated wells, equipped with seven inch or larger casing, the installation of a submersible pump is known. An existing electric submersible motorxe2x80x94progressive cavity pump installation, by way of example, may consist of the following installation sequence from the bottom of the well to the surface: an electric submersible motor pressure sensing device; an electric submersible motor; an electric submersible motor seal section; a motor gear section; a motor service section which attaches to the stator adapter and a left-hand threaded rotor adapter of the pump with an outside diameter of a three and one half inches. The pump can be attached to a two and seven eighth inch outside diameter EUE tubing and to a tubing adapter with an optional check and bleeder valve. A flat motor cable is also attached to the motor and is spliced to a power cable that runs to the surface along with the tubing. After the tubing is landed and the well sealed off from the surface, the motor cable is connected to a switchboard or variable speed converter and the motor is energized so that the pump will operate as required.
The typical electric submersible pump assembly that includes a submersible pump, an electric motor and a connection interdisposed between the pump and the motor uses the connection to allow the pump and motor to be placed in the hole and be removed from the well without separating. Prior art connections have not proved effective in preventing fishing jobs or time consuming workover jobs. Currently the whole electric submersible pump assembly must be pulled out of the hole and run back in whenever a pump failure occurs, such as when a stator or rotor must be changed.
There is a need in the industry for an electric submersible pump assembly that will allow the pump rotor or stator to be changed without pulling the motor. Such a system would decrease costs and time associated with workovers.
The present invention provides an electric submersible pump assembly with a latch device that includes a pump latch connector and motor latch connector that allows a pump and an electric submersible motor to be placed in the wellbore independently and then connected. The pump latch connector attaches to the pump and includes a rotor connector box and a stator connector pin. The motor latch connector attaches to the motor and includes a rotor connector pin and a stator connector box. The rotor connector pin is disposable in the rotor connector box and the stator connector pin is disposable in the stator connector box thus connecting the previously suspended motor and motor latch connector to the retrievable pump and attached pump latch connector.
The advantages, benefits and features of the present invention will become clear from the following detailed description and drawings when read in conjunction with the appended claims.